It’s your first day as an ophthalmology resident. You walk into the department and are immediately surrounded by sophisticated devices and machines you’ve never used, with interfaces you’ve never even seen before. You reach the office and your supervisor hands you your first task: examine a patient using the slit lamp. It’s the first day, and you're already facing one of nature’s most complex phenomena: light. It seems simple. We interact with it every day. But developing a true understanding of light has challenged the greatest minds in history – Newton, Feynman, Einstein.
Welcome to ophthalmology: a specialty where you must think like an engineer, a physicist, and a surgeon – all at once. You'll work with light constantly – from basic refraction to advanced imaging devices. And yet, as a medical graduate, your training in optics may have barely scratched the surface. You've been taught about cells, antibodies, and diseases, but little about wave-particle duality, laser-tissue interaction, or photonics. It’s disorienting and challenging when you first step in.
That was my experience during my first clinical rotation in ophthalmology as a medical student. After an exciting internship at University College London, under the supervision of Dr. Abby Wilson, an engineer and Royal Academy of Engineering Fellow, and Professor John Marshall, known for pioneering excimer laser refractive surgery, I made the unusual decision of pursuing a PhD in optics before starting residency.
Coming from a purely medical background, there were challenges and rewards alike in digging a little deeper into the world of physics in a PhD setting.
The beginner’s burden
New beginnings are always hard; they’re even harder when you jump straight into advanced optical systems, all while having no background in optics. It is one of the first and most humbling challenges, particularly for doctors. Years of medical training make you competent, knowledgeable, and confident in your abilities. But in the lab you become a complete novice again. You’re surrounded by experts – physicists, engineers, and computer scientists – who speak a completely different language than you. Diffraction? Wavefront? Young’s modulus? These are concepts that they studied very early in their curriculum, and bridging that gap requires long hours of self-study, supplementary coursework, and constant catch-up. But the beginner mindset is not always bad – it brings a new perspective of simplicity and clarity, with a clinically-driven purpose. This is valuable for impactful research.
An engineer and a physicist
The way an engineer thinks can be quite different from that of a doctor. In medicine, the focus is on adhering to evidence-based protocols. It is built for safety and repeatability. Mistakes are not allowed, and creativity isn’t necessarily welcomed in the clinical setting. This is completely different from the world of hard science. In hard sciences, you're trained very early on to ask “Why not?” instead of “What’s the protocol?” Suddenly you're no longer guided by well-established guidelines. In fact, you're often expected to challenge assumptions and invent new approaches altogether. It is important to embrace this change early on, as this will dictate your ability to accept failures along the way, a regular part of progress in experimental research.
Hypes vs. facts
As an ophthalmologist you are dealing with the latest technologies. Even the latest advances in astronomy and physics are being quickly extrapolated to ophthalmology, “aberrometry” being one example. It might be worth it to dedicate enough time to reach a good understanding of how these devices work, as this can directly impact the quality of the treatment you deliver to your patients.
For example, let’s say you have your own private practice, and you read about a new device in a journal article and then see it promoted at a conference. In the past, you might have been tempted to take it at face value – especially if it promised better outcomes for your patients. But now? You read the technical papers; you understand the underlying physics; you gauge whether it’s hype or the real deal; and only then do you decide whether you should purchase it.
Meeting innovation
John Marshall once said: “Innovation happens at the edges – where disciplines meet, not where they stay apart.” Doing a PhD in hard science allows you to gain the knowledge and expertise of an engineer and a physicist, all while keeping the practical, patient-centered mindset of a doctor. As a doctor, you understand the need, and as an engineer, you have the tools to look for solutions to that need. And this is exactly where innovation takes place.
